nixpkgs-suyu/modules/virtualisation/libvirtd.nix
Eelco Dolstra 43f43fd185 * Only stop libvirt-guests automatically on system shutdown.
Saving/restoring VMs is disruptive.

svn path=/nixos/trunk/; revision=33844
2012-04-19 15:12:55 +00:00

139 lines
3.5 KiB
Nix

# Upstart jobs for libvirtd.
{ config, pkgs, ... }:
with pkgs.lib;
let
cfg = config.virtualisation.libvirtd;
in
{
###### interface
options = {
virtualisation.libvirtd.enable =
mkOption {
default = false;
description =
''
This option enables libvirtd, a daemon that manages
virtual machines. You can interact with the daemon
(e.g. to start or stop VMs) using the
<command>virsh</command> command line tool, among others.
'';
};
virtualisation.libvirtd.enableKVM =
mkOption {
default = true;
description =
''
This option enables support for QEMU/KVM in libvirtd.
'';
};
};
###### implementation
config = mkIf cfg.enable {
environment.systemPackages =
[ pkgs.libvirt ]
++ optional cfg.enableKVM pkgs.qemu_kvm;
boot.kernelModules = [ "tun" ];
jobs.libvirtd =
{ description = "Libvirtd virtual machine management daemon";
startOn = "stopped udevtrigger";
stopOn = "";
path =
[ pkgs.bridge_utils pkgs.dmidecode pkgs.dnsmasq
pkgs.ebtables
] ++ optional cfg.enableKVM pkgs.qemu_kvm;
preStart =
''
mkdir -p /var/log/libvirt/qemu -m 755
rm -f /var/run/libvirtd.pid
mkdir -p /var/lib/libvirt -m 700
mkdir -p /var/lib/libvirt/dnsmasq -m 700
# Libvirt unfortunately writes mutable state (such as
# runtime changes to VM, network or filter configurations)
# to /etc. So we can't use environment.etc to make the
# default network and filter definitions available, since
# libvirt will then modify the originals in the Nix store.
# So here we copy them instead. Ugly.
for i in $(cd ${pkgs.libvirt}/etc && echo \
libvirt/qemu/networks/*.xml libvirt/qemu/networks/autostart/*.xml \
libvirt/nwfilter/*.xml );
do
mkdir -p /etc/$(dirname $i) -m 755
cp -fpd ${pkgs.libvirt}/etc/$i /etc/$i
done
''; # */
exec = "${pkgs.libvirt}/sbin/libvirtd --daemon --verbose";
# Wait until libvirtd is ready to accept requests.
postStart =
''
for ((i = 0; i < 60; i++)); do
if ${pkgs.libvirt}/bin/virsh list > /dev/null; then exit 0; fi
sleep 1
done
exit 1 # !!! seems to be ignored
'';
daemonType = "daemon";
};
# !!! Split this into save and restore tasks.
jobs."libvirt-guests" =
{ description = "Job to save/restore libvirtd VMs";
startOn = "started libvirtd";
# We want to suspend VMs only on shutdown, but Upstart is broken.
stopOn = "";
restartIfChanged = false;
path = [ pkgs.gettext pkgs.libvirt pkgs.gawk ];
preStart =
''
mkdir -p /var/lock/subsys -m 755
${pkgs.libvirt}/etc/rc.d/init.d/libvirt-guests start || true
'';
postStop = "${pkgs.libvirt}/etc/rc.d/init.d/libvirt-guests stop";
respawn = false;
};
jobs."stop-libvirt" =
{ description = "Helper task to stop libvirtd and libvirt-guests on shutdown";
task = true;
restartIfChanged = false;
startOn = "starting shutdown";
script =
''
stop libvirt-guests || true
stop libvirtd || true
'';
};
};
}